<div class="row">
    <div class="col" style="width: 90%;">
        <nav class="nav nav-pills flex-column flex-sm-row" style="width: 60%">
            <a class="flex-sm-fill text-sm-center nav-link" th:href="@{/}">首页</a>
            <!--<a class="flex-sm-fill text-sm-center nav-link" th:if="${session.username}!=null" th:href="@{/borrows}">借阅列表</a>-->
            <a class="flex-sm-fill text-sm-center nav-link" th:if="${session.username}==null"
               th:href="@{/login}">登录</a>
            <a class="flex-sm-fill text-sm-center nav-link" th:if="${session.username}==null"
               th:href="@{/sign}">注册</a>
            <a class="flex-sm-fill text-sm-center nav-link"
               th:if="${session.username !=null && session.username =='admin'}" th:href="@{/admin}">进入后台</a>
            <a class="flex-sm-fill text-sm-center nav-link" th:if="${session.username}!=null" th:href="@{/logout}">注销</a>
        </nav>
    </div>
    <div class="col" style="width: 5%">
        <span id="welcome" th:if="${session.username}!=null" th:text="${session.username}">123</span>
    </div>
</div>
<script>

</script>